Recent Food and Drug Administration approvals of drug-eluting coronary stents (2003) and carotid arterial stents (2004), as well as the expansions of coverage indications for implantable cardioverter- defibrillators (2003 and 2005) by the Centers for Medicare and Medicaid Services (CMS), have made hundreds of thousands of elderly Medicare beneficiaries newly eligible recipients of expensive cardiovascular technologies. These regulatory decisions entail additional expenditures of billions of dollars annually by the government on cardiovascular health care for the elderly. As new technologies are the leading driver of health care costs, policymakers have been attemping to shape the process by which new technologies diffuse into the health care marketplace. Policies such as Medicare's new "Coverage with Evidence Determination," as well as limiting coverage of some technologies to hospitals that are "high quality," are two such examples. However, there is an inherent tension between ensuring that health care technologies are used efficiently (maximizing health outcomes at minimum cost), and promoting health care equity (providing equivalent access to promising technologies to historically disadvantaged Medicare beneficiaries). To explore both ends of this tension, we will analyze national Medicare claims data from 2001-2006 in pursuit of the following goals: (1) We will describe differences across U.S. hospitals and small geographic areas in the patterns of early adoption of drug-eluting coronary stents, implantable cardioverter- defibrillators for primary prevention of sudden cardiac death, and carotid arterial stents, and determine if this variation was associated with differences in CMS policies governing technology coverage, financial incentives for technology adoption, structural/financial characteristics of hospitals, and local health system characteristics. (2) We will determine if variation in early adoption of these technologies had significant impact on the availability of these therapies in hospitals or small geographic areas with large racial and ethnic minority and/or low socioeconomic status populations. (3) We will estimate improvements in clinical outcomes and concurrent increases in costs during the first years of technology diffusion in hospitals and localities identified as early adopters, compared to those identified as slow or persistently low adopters. Relevance to public health: An unending stream of effective-but-expensive new cardiovascular devices continually and frequently enters the medical marketplace. Thus, the public has strong interests in both optimizing the process by which beneficial new technologies become available to all elderly Americans regardless of their race, location, or health system characteristics, as well as promoting efficient system-wide adoption of these new technologies so that these therapies maximize the opportunity for health benefits for all clinically-appropriate beneficiaries while minimizing the use of increasingly limited health care resources.